Hoisting apparatus



May 27, 1952 D. A. WALLACE 2,598,625

HOISTING APPARATUS Filed Nov. 4, 1948 3 Sheets-SheetI l D. A. WALLAC E HOISTING APPARATUS 3 Sheets-Sheet 2 'wir INVENTOR. ayz'J A )o/a/Zace.

May 27, 1952 Filed Nov. 4, 1948 May 27, 1952 D. A. WALLACE 2,598,625

HOISTING APPARATUS Filed Nov. 4, 1948 3 sheets-sheep;

l 6021290/ uoms' IN VEN TOR.

fraR/VIX Patented May 27, 1952 HOISTIN'G APPARATUS David A., Wallace, Grosse Pointe Farms, Mich., assigner to Weleo. lne., Detroit, Miche oorpof ration of Michigan Application November 4. 19.4.81 Serial No. .5.3319

l1,3 Claims. 1

This invention relates to improved hoisting apparatus and is an improvenrieni',v in hoisting ap.- paratus 'of the character set forth in my cepending applications Serial Nos. 15,827, i'lled March 19, 1948, and, 34,772, led. June 2,3, 1948.

More specifically the invention relates to improvements in hoisting apparatus which is particularly adapted for hoisting vehicles.

Inmy abovementioned applications there is disclosed a pair of selectively. Simultaneously and independently operable hoisting units which are adapted to be drivingly operated by a single continueus screw member. eeen unit being provided with a rolde-sable nut member that may be selectively engaged with and disengaged from the screw. While apparatus embodying such construction 'has been found to operate satisfactorily, dep'endable-releasable nut devices are expensive, difficult to Construct and have a relatively short life as compared to nut members which -are per-.- manently in threaded connection with a screw.

One of the main objects of this invention is to provide a pair of permanently, threadedly ensaged screw and nut assemblies in hoisting apparatus of this character which may be simultaneously'actuated to respectively raise and lower a pair `of hoisting units in unison with each other.

Another object of the invention is to provide a releasable clutch element between the screws of la pair of hoisting units of this character which may be selectively engaged to operate both hoisting units simultaneously or disengaged to accommodate operation of only one of said hoists ing units. v

,Another object of the invention is to provide simpled fand improved power driving mechanism which may be utilized to simultaneously operate both hoisting units and to operate only said one of said units.

A still .further object of the invention is to provide an electrical control circuit for such power driving mechanism in which is included a pair 0l? limit switch devices, onev for interrupting the operation of the power driving mechanism When the boom members of the hoisting units are in predetermined upper and lower positions, respectively, l

An additional object of the invention is to pro.- vide lcontrol apparatus Afor .engaging and disengaging 'the clutch between the refSpective screws of the hoisting units and which also serves to hold the limit switch device that limits downward movement of the boom members, against .interfering with the operation of the power .driving mechanism when the clutch is diSrlgoged $0 3S.

' tus- 2 to allow the power driving mechanism. to, be uti.- lized in shift v'said one of the hoisting units bodily relative to the other unit and to raise and lower the said one hoisting. unit While. the other remeins in. its lovvermst ooeitlolo2 An illustrative embodiment. oi the invention ie Shown in the accompanying drawings. in whioh Fig- 1 is e perspective View of vehiole hoist.- ing apparatus embodying the invention.

Fig. 2 is a transverse sectional view taken on line 2-2 of Fig. 1.

Fig.4 3 is a fragmentary longitudinal sectional View taken on line 3=3 of Fig. 1.

Fle- 4 iS e .fragmentary pleo, 'view of the Genf trai portion of the hoisting apparatus shown. in sie. .1, illustrating the respective hoietlns'iinits in their lowered positions.

Eig. 5 is a transverse sectional view taken on line '5-5 of Fig. 4.

Fig. e is a fragmentary side elevational View showing one of the hoisting units of the apparatus illustrated in Fig. 1, in a position to which it is bodily shifted to obtain a lfavorable initial mechanical advantage during the rst stages of ope eration of the hoisting unit from its lowermost position.

Fig. 7 is a transverse sectional View taken on the line 6FT of Fig. 6 and showing the structure on a somewhat larger scale.

Fig. 8 is a longitudinal, vertical sectional view taken online 878 of Fig. 4,. f

Fig, 9 is a diagrammatic view showing the Wire diagram of the control .olrouii of the power drivins'rneohenism of my improved hoisting appare.-

ll'ig. l of the drawings is illustrated hoisting apparatus embodying the invention which ,comprises hoisting units A and B each of which are substantially identical, the description of one of which will serve! in all but pertain respects hereluefter .Speoiea .for the others- These hoisting units .are partioulerly Constructed to lift yelloles but may be readily adapted to the lifting of nu.- meroue other artole's They are preferably .oreratively mounted on a track eomorleins speoed rails lo and .Il of Channel shaped orosei .Section having .inwardly feoins upper flanges l2 and .I3 and `lower .anses I4 and l5- The .rolls I9 .and .Il may be mounted in a shallow groove formed in a platform structure (not shown) Whioll may be disposed upon a floor structure or they may be mounted in e .shallow groove (not .Shower of e floor siruetiire with ille 'opper liasses l2 @ed lf3 een with the floor sono. el

The hoisting rinitis A end B efeeh iliollide a V20 and 2| are journalled on the outer end portions of trunnions 22 and 23, which are respectively mounted on and extend outwardly from end nanges 24 and 25 of the carriage I1. The end flanges 24 and 25 may be welded to or formed integral with the base plate I8 and flange I9 of the carriage I1.

Each hoisting unit includes a boom member, generally designated by the numeral 29, which comprises a pair of channel members 30 and 3| having outwardly facing web portions and provided with solid lower end portionsV 30 and 3|', respectively. The solid lower end 30' of the channel member 3|) is apertured and journalled on the trunnion 22 at a location between the wheel 29 and end ange 24, as shown in Fig. 5. The solid lower end 3| of the channel member 3| is apertured and journalled on the trunnion 23 at a location between the wheel 2| and the end flange 25.

A load receiving seat generally designatedY by the numeral 36, is pivotally mounted on the upper ends of the channel members 30 and 3| as illustrated in Fig. 1. The load receiving seat 36 comprises a channel bar 31 on the opposite end portions of each of which is shiftably mounted for movement longitudinally and transversely of the bar 31, a rubber pad 38. Provided on the opposite side of the bar 31 are spaced downwardly extending ears 39 for receiving pins 40 by which the seat 36 is pivotally mounted on the upper ends of the channel members 30 and 3|. The rubber pads 38 of the hoisting unit A may be notched to receive the rear axle of a vehicle.

When the boom member comprising the chan.- nel members 30 and 3| is in its uppermost position, the lower side of the bar 31 seats upon the upper extremities of the channel members. Dur- Y ing movement of the boom member 29 from its lower to its upper position the seat 36 is retained in a substantially horizontal position by parallelogram mechanism including link members 4I extending substantially parallel to the channel members 3D and 3| which are pivotally attached at their upper ends 'by a pin 42 to rigid arms 43 gaged between the flanges I2 and extending from the lower side of the bar 31 of the seat member, as shown in Fig. l. The lower ends of the links 4| are pivotally attached by pins l i 44 carried by ears 44 extending leftwardly from the ange portion I8 of the carriage I1. The pivotal axis provided by the pins 42 and 44 are equidistant from the pivotal axis of the seat 36 DIO- vided by the pins 40 and the pivotal axis of the boom member provided by the trunnions 22 and 23, respectively. This provides a parallelogram mechanism which retains and supports the seat 36 in horizontal load supporting position during movement of the boom member 29 between its lower and upper positions. When the boom member is in its upright position the seat 35 is supported in horizontal position by engagement of its lower side with the upper extremities of the channel members 30 and 3 I.

The boom.member 29 is supported and guided during its movements by a lever system, generally designated by the numeral 45, which includes a rigid yoke element comprising an intermediate span part 46 and spaced rigidly connected link arms 41. The span part 46 and link arms 41 may be integrally formed, welded or otherwise suitably rigidly connected. The free ends of the link arms 41 are journalled on trunnions 43 xed to and extending inwardly from the bars 36 and 3| of the boom member 29 at aligned locations intermediate the length of the bars 3E) and 3|. Provided on the span part 46 of the yoke are spaced bearings 49 on which are journalled the upper end portions of a pair of levers 59. As shown in Fig. l the levers 59 are straight throughout the maj or portions of their length but are provided with slightly upwardly curved upper end portions. The lower ends of the levers 56 are pivotally attached to a cross bar 5| which extends between the rails I0 and II of the track structure. This cross bar is provided with upwardly extending shoes 52, one of which is en- |4 of the rail I9 and the other of which is engaged between the anges I3 and I5 of the rail The cross bar 5I includes integral upwardly extending pairs of flanges 53 and 54 and a central bearing portion 55 having a bore 56. The lower end of one lever 5D is received between the flanges 53 and pivotally' attached thereto by a pin 51 and the lower end of the other lever is received between the anges 54 and pivotally attached thereto by a pin 58. The cross bar 5| is preferably releasably xed to the side rails I0 and II by pins 59 or other suitable means such as bolts, capscrews and the like. The bars 39 and 3| of the :boom 29 are adapted to be received between the shoes 52 and the adjacent anges 53 and 54 respectively when the hoist is in its lower position.

The hoisting unit B is substantially identical to the hoisting member A and similar parts are designated by the same numeral. However, the lower ends of the levers 5U of the hoisting unit B are pivotally attached to a cross bar 5I which is substantially identical to the cross bar 5I of unit A. Provided on the cross bar 5I' are pairs of upstanding flanges 63 and 64. The lower end of one lever` 50 is received between the flanges 63 and pivotally attached thereto by a pin 65 and the lower end of the other lever 59 is received between the iianges 64 and pivotally attached thereto by a pin 65. The cross bar 5I' has an upstanding side flange 61 extending along its left-side, as viewed in Fig. 4, on the left side surface of which is provided spaced pairs of ears 63. Between each pair of ears 63 is pivotally mounted a dog 69 which is engageable between teeth of a rack 10, one of which is stationarily mounted adjacent each rail I9 and I I, respectively. The dogs 69 are connected together by a bar 1| by which they may be simultaneously pivoted out of lengagement with the-rack 10 when it is desired to release hoisting unit B for movement relative to hoisting unit A. In this Way the apparatus may be conditioned for shifting loads of direrent lengths.

As each boom member 29 approaches its lower position, the links and arms 41 reach the relative ypositions shown inFig. '1 and further lowering movement brings these members into approaching alignment. A spring 93' is tensioned during movement of the levers 50 and links 41 towards'an aligned condition. This spring serves to shift the levers out of alignment when the boom members are raised.

The driving apparatus by which the boom members 29 of the hoisting units A and B may be simultaneously positively raised and lowered and by which only the boom member of the hoisting nnit'B 'may ce operated if desired, comprises av pair ci aligned screw elements 13 and 14; rase soc-lated with the hoisting urllts'll and B, respeca tively. 'The screw element I3 is` journaled vat one end the bore `5t ofthe bearing portion 55 on the cross member 5| and it is held against axial movement by thrust resisting collars 15 fixed to the screw 13 which engage thrust bearings 16 moiited iiippsiteeitemities of the bearing portion 55. 7lhe other end of the screw element isis journaled in a bore vtanned in a cross membei"F 16 Wliih 'eteidsbtween and is fixed te the rails f| 0 and Il. 'The screw element 14 is Jourd naled at' 'one ehd Pia bearing 'l1 mounted 6h 'a crs`-meiber 18 Whih connects the rails 'IUand I I and at its other end in a bearing 19 merited on a cross member which loins' the right end portions of the'rails lu and u. A

'The adjacent ends of the screw elements 13 and 14 are disengageably connected together by a. clutch, generally designated by the numeral 0|, which lincludes a clutch element v82 'fixed to the 'right end of the screw element 13,' as` viewed in Figs. l and 4, and `a shiftable clutch element 83 which is s'plined on the left end of the-Screw element 14. The clutch element 8'3 is provided with an operating lever 84 which is pivotally mounted at 85 on the rail I9 and operatively connected at its intermediate portion to the clutch element 8'3. 'lhe intermediate portion vof the lever 81| is enlarged and provided with an opening in which the right end portion of the clutch element is received. The lever 81| is pivotally co nectedfwith a slit ring 82|' seatedv in a groove 05" 'formed in the clutch element '09, by pins 8 "which loosely fits in apertures formed in the lever VBil. The free end of the lever V7BII extends through a 'slot in the rail |I vand may be rotated manually in a clockwise direction, as viewed in Fig. 4, to engage the clutch elements 02 and 93 and in a couhterclockwise direction to disengage them. 'he carriage l1 of each 'hoist-r ing unit A and respectively, is provided with a nut member 06 in which one of the screw ele* ments 13 and 14 are threaded. K A

The screw elements 13 and 14 may be driven in respectively opposite directions by aV reversible motor 01 which is drivingly connected with the right end of the screw element 10, as viewed Fig. l, -by ja chain 80 which is engaged on a sprocket '80' iix'ed to the screw" 14 and on a sprocket e9 'fined on the shafft of the motor. The motor vB1 'is provided vwith a control circuit, shown in Fig. 9 inwhich is included a portable switch box, generally designated in Fig. l bythe numeral 90. The control circuit includes a 110 volt Supply circuit comprising conductors'v 9| and s2, of which conductor 9| is connected to directly to terminals 03l and 94 of a pair of push button switches generally designated and '96, respectively. The 'switch 95 when closed prod'll'S lIWal'd 'v'met f the bOn 'lnblS 29 and the switch 96 produces downward 'movement thereof in va manner hereinafter more clearly set forth. The Switch Sillas a terminal 91 which .is connected by a conductor '93 with a movable cdntact element 99 of a limit switchy generally designatedbyy the numeral |90, which is also designated by the vlegend Limit ySwitch Stop Down. The movable -contact'99 @f this limit switch vis preferably pivotallymounted at its right end and yieldably 'urged byaspring 10| in a counterclookwise direction. TheY movable contact element u99 of the limit v'switch |00 is alternatively 'engageable with terminals |02 and i |03. Therspring `|0| normally urges the movable coi'itactelement 99 of the' Switch |00 into engagement with the terminal |03 but as shown in Fig. 9, the movable contactv element 99 is adapted to be engaged with the terminal |02 by a cam '|04 which engages a follower |05 attached to the Lmovable contact element 99. The terminal v|02 of the limit switch |00 is connected by a conductor |06 and |01 with one terminal of a signal such as a bell |08 and the other terminal 'of the bell is connected with the conductcr 92 of the power supplyr line. The terminal |03 o the limit switch |00 is connected by a conductor |09 with a relay ||0 that estabiishes' rotation of 'the motor 81 in a direction to 'produce downward movement of the boom melbs.

|00 is located on the .rail l0, with its follower |05a'ira`nged to be engaged by the cam |04 which is carried by the carriage I1, when the boom member 29 of hoisting unit A is in its predetermined lowernos't position. As long as the push button switch '90 iis depressed and the movable Contact' 99 is engaged with the fixed terminal |09,` the relay l|0 is energized to maintain the motor 01 in operation to 'drive the boom` members downwardly. When the movable contact 99 lis vdisrengaged from the terminal |193 and shifted into contact with the 'terminal |02 by the cam |04-, downward drive or the boom members by the motor 'is discontinued and the lbell |08 rings to war-n the operator that the boom members 'are `down and to advise him to discontinue "depression ci the push button switch 95. The boom members vmay be stopped in any position 'between 'their upper and lower 'positions by merely rel'as'ig th push bltto'n switch Se.

Hitli-lg' limit A, le valso provided lWith an llp limit switch, generallyV designated by the numeral ylllrwnich includes a movable contact element ||2 lgeii teriiiials H3 and I`|4 and a cam follower H5. The upf/limit switch iS mounted on the rail |`0 en the left side of the carriage I1 which is prvided with a leftwardly 'extending caml. The Vlilovable Contact element H2 is no1-finally y'ie'ldi'ibly urged into engagement with the terminal H0 by a spring ||1. The terminal lll iefconneeted by 'a vconductor'III! to a relay H9 which produces Adriving of the motor 01 in an opposite direction to that produced by the relayv I|9 in order to drive the boom members upwardly. When the push button switch 95 is closed, clrrent is supplied from its terminal |20 through aconduc'ter |21, movable contact element |I2, terminal H4 and conductor IIS to the relay II9 which establishes upward driving of the boom members 29 by the motor 81. When the boom member 29 oi 'hoisting unit A reaches a .predetermined yupper position the cam ||0 engages the 'follower ||5 and rotates the movable contact element out of engagement with the terminal llt and into engagement with the terminal H3 `rwhich isfconnected with conductors |06l and 101 leading to the signal |08. This action thus discontinues upward driving oi the boom members 29 andactuates the signal |08 to advise the operator that the boom meinbers are in their upper positions. The up push button 95 may be released at any time during upward movement of the boom members to discontinue Such upward movement at any selected elevation of i the boom members.

Icam |4014 whichV operates the down limit switch |00 may be rendered inoperative to shift 7 the movable contact element 99 from engagement with the fixed terminal {03 into engagement with the fixed terminal IQZ, by an arm 22 rigid with lever 84 which is shown in Figs. 4 and 9. The arm |22 is arranged to engage the cam |84 when the lever 84 is rotated in counterclockwise direction and to deflect it away from the follower H35 as such rotation of `the lever 8f! disengages the clutch elements 82 and Therefore, when these clutch elements are disengaged the limit switch |80 is always set to allow its movable contact elementJ 99 to remain inj contact with the terminal H13 even though the boom member 29 of hoisting unit A is in itsk lowermost position. When the boom member of hoisting unit A is in any position below its upper predetermined position the movable contact elementV H2 of the limit switch HI is in the position shown in Fig. 9, and thus, while these conditions exist and while the clutch 8| is disengaged the push buttons 95 and 96 can be utilized to produce up and down movements of only the boom member of the hoisting unit B.

While both of the boom members of the hoisting units A and B are in their lower positions, and the clutch 8l is disengaged and the cam m4 is held in an inoperative position, the rotation of the screw element 74 in respectively opposite directions under the control of the push buttons 95 and 96 may be relied upon to drivingly shift the hoisting unit B in correspondingly opposite directions relative to the hoisting unit A. This is accomplished by lifting the bar H and associated'dogs 69 and holding the latter out of engagement with the teeth of the rack 'I0 while adjustment of the hoisting unit B is produced.

The boom members of the two hoisting units may be simultaneously operated by simple driving mechanism of inexpensive constructions which can be conveniently conditioned with the aid of a common clutch to operate only one hoisting unit. The same driving mechanism can be Y utilized to drivingly shift one hoisting unit relative to .the other and the limit switch control mechanism and signal, which saves the operator from closely watching the actions of two hoists, is automatically conditioned, when the clutch of the driving mechanism is disengaged, to allow one screw element to either raise and lower one :boom member or to shift one hoisting unit relative to the other.

Although but one specific embodiment of the invention is herein shown and described, it will be understood that various changes in the details and construction thereof may be made without departing from the spirit and scope of my invention.

I claim:

ll Vehicle hoisting apparatus including a support, a pair of hoisting units mounted on said support, each including a boom member shiftable between upper and lower positions, means for drivingly shifting said boom members including a pair of screw elements each operatively coni nected with one of said boom members respectively, a releasable clutch for selectively connecting and disconnecting said screw elements to permit simultaneous shifting of said boom members and shifting of only one thereof respectively, and manually operable control mechanism for selectively engaging and disengaging said clutch. l

2. Vehicle hoisting vapparatus including a support, a pair of hoisting units mounted on said support, each including a boom member shiftable between upper and lower positions, a threaded nut element on each of said hoisting units respectively, means for drivingly shifting said boom members including a pair of screw elements each independently rotatably mounted on said support in permanently threaded engagement with one of said nut elements respectively, one end of each of said screw elements being adjacent each other, a releasable clutch for selectively connecting and disconnecting the adjacent ends of said screw elements to permit simultaneous shifting of said boom members and shifting of only one thereof respectvely,.manually operable control mechanism for selectively engaging and disengaging said clutch, and power driving mechanism operatively connected with one of said screw elements.

3. Vehicle hoisting apparatus including a support, first and second hoisting units mounted on said support in spaced relation with respect to each other, each including a boom member shiftable between upper and lower positions, a first screw rotatably mounted on said support and threadedly connected with the boom member of said first hoisting unit, mechanism for drivingly rotating said first screw element,- a second screw rotatably mounted on said support in substantially axial alignment with said first screw and threadedly connected with the boom member of said second hoisting unit, means bodily shiftably mounting said rst hoisting unit on said support for bodily movement relative to said second hoisting unit and longitudinally relative to said support and screw, releasable anchoring means coacting between said support and said first hoisting unit forV fixing said first hoisting unit in selected positions relative to said second hoisting unit to accommodate lifting of vehicles of different lengths, and a releasable clutch for positively connecting together the adjacent ends of said aligned screw.

4. Vehicle hoisting apparatus including a support, first and second hoisting units mounted on said support in spaced relation with respect to each other, each including a boom member shiftable between upper and lower positions, a first screw rotatably mounted on said support and threadedly connected with the boom member of said first hoisting unit, mechanism for drivingly rotating said first screw element, a second screw rotatably mounted on said support in substantially axial alignment with said first screw and threadedly connected with the boom member of said second hoisting unit, means bodily shiftably mounting said first hoisting unit on said support for bodily movement relative to said support and screws and saidv second hoisting unit, releasable anchoring means coacting between Said support and said first hoisting unit for fixing said first hoisting unit in selected positions relative to said second hoisting unit to accommod'ate lifting of vehicles of different lengths, and means for selectively drivingly connecting and disconnecting the adjacent ends of said screws for simultaneously operating both of said screws and only said first screw respectively, said first hoisting unit being bodily shiftable relative to said screws and said support by said rst screw when said screws are disconnected and said anchoring means are released.

5. Vehicle hoisting apparatus including a support, a pair of hoisting units mounted on said support, each including a boom member shiftable between'upper and lower positions, means for drivingly shifting said boom members between said upper and lower positions including a pair of series related ractuating elements one operaing said power driving mechanism in forward and Yreverse directions to respectively raise and lower i said boom members, limit switch means in said circuit responsive to downward movement of one Vof said boom members for interrupting reverse `drive of said driving mechanism, and a control member Yfor said connecting and disconnecting -means including an element for rendering said limitA switch means inoperative to interrupt reverseoperation of said driving mechanism when y said control member is shifted to disconnect said actuating members.

12. Vehicle hoisting apparatus comprising a base structure, a pair of boom members mounted on said base structure in spaced relationship for shifting movement between generally vertical and lgenerally horizontal positions, mechanism asso- Sciated with each of said boom members for the action of said lever member including a pair of driving members and means for permanently operatively connecting each of said boom members with one of said driving members respectively and connecting means between said driving membersincluding a releasable element for selectively connecting and disconnecting said driving members to operate both of said boom members simultaneously and to operate only one of said boom members respectively.

13. Vehicle hoisting apparatus comprising a base structure, a pair of boom members mounted on said base structure in spaced relationship CFI 12 for shifting movement between generallyve'rtical and generally horizontal positions, mechanism associatedwith each of said boom members for vshifting it between said positions including a lever element and means operatively connecting one end of said lever element to said boom member, means for .relatively shifting each boom member and the other end of each lever element in opposite directions for respectively raising and lowering said boom member through the action of said lever elements, said means including a pair of series related actuating elements one for shifting each of said boom members respectively, and a releasable clutch for selectively connecting and disconnecting said actuating elements to operate both of said boom -members simultaneously and to operate only one of said boom members respectively, said actuating elements each in- `cluding a screw and means threadedly connecting it with one of said boom members respectively.

DAVID A. WALLACE.

REFRENCES CITED The'following references are of record in the le of this patent:

' VUNITED STATES PATENTS Number Name Date 1,725,216 Seldomridge Aug. 20, 1929 1,745,048 Romine Jan. 28, 1930 1,754,873 Blackwood Apr. 15, 1930 2,015,357 Weaver Sept. 24, 1935 FOREIGN PATENTS Number Country Date 27,710 Netherlands July 16, 1932 

